The "friction stiffness" setting in the configuration file does not directly affect dynamics. This value is used only in the static analysis.
Indirectly however, the "friction stiffness" does have an effect. The reason is that in a non-liinear analysis, you must select a static load case to set the non-linear restraint status (this is the first entry on the "Control Parameters" dialog). The results of the static load case selected depend on the "friction stiffness".
If you want to include friction effects in dynamics, make sure you set the "stiffness factor for friction" on "Control Parameters" dialog. This is a multiplier used to compute a spring, simulating the effects of friction. The "spring stiffness" is determined as:
k = "stiffness factor for friction" * N * mu, where "N" is the normal force load on the restraint from the "static load case" you referenced, i.e. "static load case for nonlinear restraint status".
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Regards,
Richard Ay - Consultant